US3572447A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Torque measuring system for impact wrench
Assignee: Ingersoll Rand Co
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Filing: 1968-11-12
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Granted: 1971-03-30
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Expires: 1988-11-12
Abstract
Abstract An impact wrench including a resilient member disposed between the motor and the fastener driving spindle and adapted to yield under torque to measure the torque load. The torque load on the resilient member is measured by means such as an electrical strain gauge which operates a valve to stop the tool in response to the rise of the torque load to a selected magnitude.
Inventors
- 👤 Reginald W Pauley
- 👤 Leo Kramer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:17
CPC Classifications
B; B25; B25B; B25B23/00; B25B23/14; B25B23/145; B25B23/1453; B25B23/1456
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
100 words
A system for measuring the torque output in an impact wrench including a motor and a rotary impact mechanism connected to a spindle adapted to deliver a series of rotary impacts to a fastener, the invention comprising: a flexible member interconnected between the motor and spindle and operative to flex in direct proportion to the change of torque load on the spindle; and an electrical strain gauge attached to said flexible member and operative to measure the strain in said flexible member and to create an electrical signal in response to said strain to indicate the torque on said spindle.
Claim 2
Independent Claim
100 words
A system for measuring the torque output in an impact wrench including a motor and a rotary impact mechanism connected to a spindle adapted to deliver a series of rotary impacts to a fastener, the invention comprising: a flexible member interconnected between the motor and spindle and operative to flex in direct proportion to the change of torque load on the spindle; and an electrical strain gauge attached to said flexible member and operative to measure the strain in said flexible member and to create an electrical signal in response to said strain to indicate the torque on said spindle.
Claim 3
Dependent Claim
28 words
The system of claim 1 including; means responsive to said signal to stop said motor upon the torque load on said spindle rising to a predetermined torque level.
Claim 4
Dependent Claim
18 words
The system of claim 1 wherein; said flexible member is interconnected between the motor and the impact mechanism.
Claim 5
Dependent Claim
18 words
The system of claim 1 wherein; said flexible member is interconnected between the impact mechanism and said spindle.
Claim 6
Dependent Claim
24 words
The system of claim 1 wherein; said flexible member is maintained under an adjustable predetermined torque load prior to the use of said wrench.
Claim 7
Dependent Claim
22 words
The system of claim 1 wherein; said electrical strain gauge is connected by conductors to a Rotary electrical connection and an amplifier.
Claim 8
Dependent Claim
26 words
The system of claim 6 wherein; said amplifier is operative to shut off the wrench motor in response to the signal received from said strain gauge.
Claim 9
Dependent Claim
18 words
The system of claim 7 wherein; said amplifier operates a fluid valve means to shut off the motor.
Claim 10
Independent Claim
128 words
A system for measuring the torque output in an impact wrench including a motor, a rotary impact mechanism and a spindle adapted to deliver a series of rotary impacts to a fastener, the invention comprising: a yieldable member interconnected between the motor and the impact mechanism and adapted to yield in response to the torque load on the spindle; resilient means opposing the yielding of said yieldable member under a torque load; means applying a preload to said resilient means preventing said yieldable member from yielding further until the torque load on said spindle rises above a predetermined value; and means for creating an electrical signal in response to further yielding of said yieldable member thereby indicating that the torque load has risen above said predetermined torque load.
Claim 11
Independent Claim
128 words
A system for measuring the torque output in an impact wrench including a motor, a rotary impact mechanism and a spindle adapted to deliver a series of rotary impacts to a fastener, the invention comprising: a yieldable member interconnected between the motor and the impact mechanism and adapted to yield in response to the torque load on the spindle; resilient means opposing the yielding of said yieldable member under a torque load; means applying a preload to said resilient means preventing said yieldable member from yielding further until the torque load on said spindle rises above a predetermined value; and means for creating an electrical signal in response to further yielding of said yieldable member thereby indicating that the torque load has risen above said predetermined torque load.
Claim 12
Dependent Claim
22 words
The system of claim 9 wherein; said signal is created by an electrical strain gauge measuring the strain of said yieldable member.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-03-29 | 1974-09-28 | 1975-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-29 | 1978-09-28 | 1979-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-29 | 1982-09-28 | 1983-03-30 | $7700.00 | Window Closed / Lapsed |